The DS2890 is a digitally controlled potentiometer with a linear taper of 256 taps. Device control operations, including wiper positions, are ultimately simple over a single-contact 1-Wire bus electrical interface. With a wide 0-11 volt potential operating voltage range terminal, the DS2890 is ideal for a wide range of industrial and control applications. The potentiometer terminal voltage is independent of the device supply voltage and the voltage applied to the other potentiometer terminals. Communication with the DS2890 follows the Dallas Semiconductor standard 1-Wire protocol and can be implemented with minimal hardware, such as a single port pin microcontroller. Multiple DS2890 devices can reside on a common 1-Wire bus and operate independently of each other. Each DS2890 has its own unalterable 64-bit ROM registration number that is factory etched into the chip. Registration numbers are guaranteed to be absolutely unique identification numbers, traceable and used to address equipment in a multipoint 1-Wire network environment. The DS2890 will respond to a 1-Wire conditional search command if the potentiometer wiper is set to the power-up default position. This feature allows the bus master to easily determine if a potential is required to undergo a power-on reset and reconfigure the desired wiper position setting. The DS2890 supports two power modes: the device's power supply is the only mode in which parasitic 1-Wire is supplied from the 1-Wire bus or the VDD power is supplied from an external power supply, the VDD mode operates with reduced wiper resistance.